Identification of performance and cost in a new backwash method to clean the UF membrane : backwashing with low dosage of NaClO

© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature..

Ultrafiltration (UF) is widely used in wastewater reclamation treatments. Conventional backwashing is usually performed at regular time intervals (10-120 min) with permeate and without the addition of chemicals. Chemical enhanced backwashing (CEB) is usually applied after 70-90 filtration cycles with added chemicals. These cleaning methods cause membrane fouling and require costly chemicals. Instead of conventional backwashing, we propose herein a new backwashing method involving backwashing the effluent with low doses of sodium hypochlorite (NaClO) named as BELN. The performance and cost of UF backwashing were investigated with Beijing wastewater reclamation treatment. The results showed that the transmembrane pressure (TMP) increased from 33.2 to 48.2 kPa during hydraulic backwashing after 80 filtration cycles but increased from 33.3 to 39.3 kPa during backwashing with a low NaClO content of 20 mg/L. It was also noticed that the hydraulic-irreversible fouling index decreased from 5.58 × 10-3 m2/L to 3.58 × 10-3 m2/L with the new method. According to the three-dimensional fluorescence excitation-emission (3D-EEM), the response increased from 11.9 to 15.2% with BELN. Protein-like material was identified as the main component causing membrane fouling by blocking the membrane pores. The results indicated that the low dosage of NaClO effectively stripped the fouling layer. Finally, based on an economic evaluation, the capacity of the UF process was increased from 76,959 to 109,133 m3/d with the new method. The amount of NaClO consumed for Beijing wastewater reclamation treatment was similarly compared with the conventional backwashing in per year under BELN. The new method has good potential for application.

Medienart:

E-Artikel

Erscheinungsjahr:

2023

Erschienen:

2023

Enthalten in:

Zur Gesamtaufnahme - volume:30

Enthalten in:

Environmental science and pollution research international - 30(2023), 58 vom: 27. Dez., Seite 121983-121992

Sprache:

Englisch

Beteiligte Personen:

Yang, Lian [VerfasserIn]
Qiu, Haoran [VerfasserIn]
Lu, Zixin [VerfasserIn]
Zhang, Chunrui [VerfasserIn]
Liu, Guoliang [VerfasserIn]
Chang, Jiang [VerfasserIn]
Wu, Congcong [VerfasserIn]
Dong, Shuoxun [VerfasserIn]
Yang, Shaoxia [VerfasserIn]
Xiao, Feng [VerfasserIn]

Links:

Volltext

Themen:

Backwash
Cost
Journal Article
Membrane fouling
Membranes, Artificial
Sodium hypochlorite
Ultrafiltration
Wastewater

Anmerkungen:

Date Completed 18.12.2023

Date Revised 27.12.2023

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1007/s11356-023-31008-3

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM364557540